/*
 * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
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 *
 */

package javax.xml.xpath;

import java.net.URL;
import java.security.*;
import java.net.*;
import java.io.*;
import java.util.*;

/**
 * This class is duplicated for each JAXP subpackage so keep it in sync.
 * It is package private and therefore is not exposed as part of the JAXP
 * API.
 *
 * Security related methods that only work on J2SE 1.2 and newer.
 */
class SecuritySupport {


  ClassLoader getContextClassLoader() {
    return (ClassLoader)
        AccessController.doPrivileged(new PrivilegedAction() {
          public Object run() {
            ClassLoader cl = null;
            try {
              cl = Thread.currentThread().getContextClassLoader();
            } catch (SecurityException ex) {
            }
            return cl;
          }
        });
  }

  String getSystemProperty(final String propName) {
    return (String)
        AccessController.doPrivileged(new PrivilegedAction() {
          public Object run() {
            return System.getProperty(propName);
          }
        });
  }

  FileInputStream getFileInputStream(final File file)
      throws FileNotFoundException {
    try {
      return (FileInputStream)
          AccessController.doPrivileged(new PrivilegedExceptionAction() {
            public Object run() throws FileNotFoundException {
              return new FileInputStream(file);
            }
          });
    } catch (PrivilegedActionException e) {
      throw (FileNotFoundException) e.getException();
    }
  }

  InputStream getURLInputStream(final URL url)
      throws IOException {
    try {
      return (InputStream)
          AccessController.doPrivileged(new PrivilegedExceptionAction() {
            public Object run() throws IOException {
              return url.openStream();
            }
          });
    } catch (PrivilegedActionException e) {
      throw (IOException) e.getException();
    }
  }

  URL getResourceAsURL(final ClassLoader cl,
      final String name) {
    return (URL)
        AccessController.doPrivileged(new PrivilegedAction() {
          public Object run() {
            URL url;
            if (cl == null) {
              url = Object.class.getResource(name);
            } else {
              url = cl.getResource(name);
            }
            return url;
          }
        });
  }

  Enumeration getResources(final ClassLoader cl,
      final String name) throws IOException {
    try {
      return (Enumeration)
          AccessController.doPrivileged(new PrivilegedExceptionAction() {
            public Object run() throws IOException {
              Enumeration enumeration;
              if (cl == null) {
                enumeration = ClassLoader.getSystemResources(name);
              } else {
                enumeration = cl.getResources(name);
              }
              return enumeration;
            }
          });
    } catch (PrivilegedActionException e) {
      throw (IOException) e.getException();
    }
  }

  InputStream getResourceAsStream(final ClassLoader cl,
      final String name) {
    return (InputStream)
        AccessController.doPrivileged(new PrivilegedAction() {
          public Object run() {
            InputStream ris;
            if (cl == null) {
              ris = Object.class.getResourceAsStream(name);
            } else {
              ris = cl.getResourceAsStream(name);
            }
            return ris;
          }
        });
  }

  boolean doesFileExist(final File f) {
    return ((Boolean)
        AccessController.doPrivileged(new PrivilegedAction() {
          public Object run() {
            return new Boolean(f.exists());
          }
        })).booleanValue();
  }

}
